Unreasonable memory usage under linux with a simple loop

[ming_cuhk]

Hi all, I'm new to here and python.
When I tried the code below to test python's speed...
I found that python use more than 1.5G memory to run this and cost
several minutes.... And this happened only under my linux os. Both
jython and python...  Is there something wrong with python under linux
or my code?
Thanks!

a = 0
for i in range(100000000):
    a = a + 1
print a